已知x,y,z>0 求证:xy(x+y)+yz(y+z)+zx(z+x)>=6xyz
已知x,y,z都是正数,且xyz=1,求证:xy(x+y)+yz(y+z)+zx(z+x)》6
分解因式:xyz-yz-zx-xy+x+y+z-1
已知三个数x,y,z,满足xy/x+y=-2,yz/y+z=4/3,zx/z+x=-4/3,求(xyz)/(xy+yz+
正实数x,y,z满足9xyz+xy+yz+zx=4,求证:
若x+y+z=6,xy+yz+zx=11,x^3+y^3+z^3-3xyz
已知xyz都小于1,xy+yz+zx=1 求证:y/(2-X乘根号3)+z/(2-Y乘根号3)+x/(2-Z乘根...
xy+yz+zx=1,x,y,z>=0
已知X,Y,Z都是整数且xy+yz+zx=1,求证x+y+z>=根号3
XYZ满足XY/X+Y=-2,YZ/Y+Z=3/4,ZX/Z+X=-4/3,求XYZ/XY+YZ+ZX的值
已知实数xyz满足x+y+z=5,xy+yz+zx=3,求z的最大值
(x-3y+z)^2+/ 5x-4y+z/=0 且xyz≠0 xy+yz+zx/x^2+y^2+z^2
已知x+y-z=0,2x-y-8z=0,且xyz不等于0,则x2+y2+z2/(xy+yz+zx)等于